<template>
  <h2>当前求和为：{{ sum }}</h2>
  <button @click="sum++">点我+1</button>
  <hr />
  <h2>当前的信息为：{{ msg }}</h2>
  <button @click="msg += '！'">修改信息</button>
  <hr />
  <h2>姓名：{{ person.name }}</h2>
  <h2>年龄：{{ person.age }}</h2>
  <h2>薪资：{{ person.job.j1.salary }}K</h2>
  <button @click="person.name += '~'">修改姓名</button>
  <button @click="person.age++">增长年龄</button>
  <button @click="person.job.j1.salary++">涨薪</button>
</template>

<script>
import { ref, reactive, watch } from "vue";
export default {
  name: "Demo",
  setup() {
    //数据
    let sum = ref(0);
    let msg = ref("你好啊");
    let person = ref({
      name: "张三",
      age: 18,
      job: {
        j1: {
          salary: 20,
        },
      },
    });

    console.log(person);
    // 监视基础数据类型
    watch(sum, (newValue, oldValue) => {
      console.log("sum的值变化了", newValue, oldValue);
    });
    // 监视对象数据类型（对象类型需要加.value 监视代理的实例对象）
    watch(
      person,
      (newValue, oldValue) => {
        console.log("person的值变化了", newValue, oldValue);
      },
      { deep: true }
    );

    //返回一个对象（常用）
    return {
      sum,
      msg,
      person,
    };
  },
};
</script>

